Radial vane pump



March 13, 1951 N. F. MaOMlLLlN ET AL 2,545,238

RADIAL VANE PUMP Filed Aug. 7, 1944 3 Sheets- Sheet l lEl INVENTORSNorman F. Mac/mum,

? E /Iowan Puncgm I ATTORNEYS March 13, 1951 N. Fl MaGMILLIN ET AL2,545,238

RADIAL VANE PUMP Filed Aug, 7, 1944 5 Sheets-Sheet 2 INVENTORS NORMAN F.MAcMlLLIM BY HOWARD MPURCELL,

4v ATTORNEYS N. F. MacMlLLlN ET AL RADIAL VANE PUMP 3 sheets sheet FiledAug 7' 944 V INVENTORS NORMAN I. MACMILLIN,

BY Now/m0 MPURcELL, .9-

4 W ATTOR YS Patented Mar. 13, 1951 UNITED STATES PATENT OFFICE RADIALVANE PU'MP Norman MacMillin and Howard M. Purcell, Mount Gilead, Ohio,assignors to H-P-M Development Corporation, Wilmington, DeL, acorporation of Delaware Application August 7, 1944,,SerialiNo.548,334

7 Claims. 1

This inventionrelatesitofluid.operable apparatus and, particularly, tofluid operable ,pumps or motors. More particularly still this inventionrelates to vanetypepumps or motors.

It is a primary object of the present invention to provide a vane pump.or motor in which the wearing action which normally takes place betweenthe'ends of thesaid vanes-and a cylinder within which they are .movableis substantially eliminated.

It'is another object of this invention to provide .an improvedconstruction "for a vane type pump or .motor .in which the variouscomponents are readily manufactured .to the necessary tolerances withoutthe use .of special and expensive machinery.

.Itisanolther obiectto provide a vanepump or motor structure "in whichthebearing load of the vanes -in .the rotor is reduced thereby toinhibit sticking .of .the vanes and excessive wear.

It is another object to provide a variable delivery vane pump embodyingthe foregoing .improvements.

These and other objects and advantages will become more apparentupon'reference to the following-description taken in connection with theaccompanying drawings, in which:

Figure 1 is-a longitudinal section through a pump ormotor constructedaccording to this invention;

Figure .2 is a transversesection through the .pump ormotor and isindicated by theline'2-.2

on Figure 1;

"Figure 3 is a sectional view indicated by the line 3--'3 on Figure 2'and'shows the port in the cylinder block;

Figure 4 is aplan view taken over one .of the vanes of the pump or motorshowing its relationship to thesguidewalls on either side thereof Figure5 is a view of thepi'ston-Vane illustrating the action of 'the balancingsurfacesthereof;

Figure 6 is a transverse view through a modi- ..fied structure showingareversible variable discharge type of pump constructed according tothis. invention;

Figure 7 is a sectional view indicated by the line 1-1 on Figure 6 andshows a modified manner .of..retaining the .piston vanes in their,proper location; and

Figure 8lis a plan vie wover the, pistonvanein Figure 7 showing its..relationship to :the guidewalls on either side thereof.

General arrangement A pump or motor constructed according-to thisinvention comprises, generally, a casing within which'is rotatablymounted a rotor having bores therein for receiving reciprocating vane--members. The vanemembersare..adapted toride on theinnersurface -ofza-rcylin'drically bored lmem- 2 her which is eccentric with the saidrotating member.

In order "to eliminate or inhibit the wearing of the vanes where theycontact the cylinder wall, the vanes are provided with balancingareashy- .draulically-connec'ted so that the vane is continuously in .astate of hydraulic balance. When the vane is passing through a Workingzone and one side thereof is under working pressure and the othersidethereof is underrsuction pressure, afirst balancingarea is hydraulicallyconnected to the pressure side to balance Off the thrust therefromwhilea second balancing area is con- -nected with the suction side sothat any thrust therefrom is balanced-off.

According to this invention, when the device is operated as a pump, thevanes are maintained in contact with the cylinder wall by centrifugal.force .as the rotating member is driven. If the deviceis to be operatedas a motor it is necessary to urge the vanes outwardly by suitableyielding means such as springs, by hydraulic pressure or, by.a.mechanical actuator.

.The pump or motor may be made to have variable displacementby-arranging the cylindrically bored-member within the casing so thatthe relative eccentricity of the rotor .and the cylinder bore may bevaried by any arrangement of suitable and well known controls.

The vane membersare preferably cylindrical, thus simplifying themachining thereof and also provide for a greater area of contact betweenthe said vanelmembers and the 'bores in the rotor within which theyreciprocate. This inhibits wear and provides for a more readilyreciprocable vane.

Structural arrangement Referring more particularly to the drawings, thepump comprises a main body portion 5 0 which is hollow'to receive arotor II and which is also bored to receive an antifr'iction bearing l2within which the said rotor is journalled. The body .10 is engagedby acover plate or closure member 1-3 which is secured in place'by anysuitable means such as the screws Hi. 'The member l3 may be "flangedtoprovide amounting base for the pump "and, to this end,.may comprise thecountersunk "screw :h'o'l'e's 15. Similarly to the body Ill, the member13 is bored to receive an antifriction hearing which, together with thebearing I 2 serves as a support for the rotor H. The rotor 11 comprisesa first member I! which has integral 'therewith the trunnion portion 18adapted to be received within the bearing l2 and, a second :member H!which has integral therewith the trun- .nion portion :20 adapted to bereceived within the bearing I6. The member l9 also comprises.dfiven..-from-;any-suitabl :source.

The rotor members I1 and H) are secured together by a plurality ofscrews 22 which pass through the former and into threaded engagementwith the latter. Arranged between the members I! and I9 is a block 23having a plurality of shouldered bores 24 therein within which areslidably mounted a plurality of pistons or vanes 25.

The block 23 is machined so as to have parallel faces thereon whichengage correspondingly machined faces on the members H and I8. Thus,when the block 23 is placed between the members l1 and i9, and thelatter are secured together by the screws 22, the said members areexactly and positively spaced apart.

Disposed around the block 23 is a cylinder block 26 which has parallelfaces thereon which exactly and slidably fit between the faces of themembers i! and IS. The block 26 is provided with an eccentric bore 28,as shown in Figure 2, and is, likewise, provided with the bores 29 oneither side thereof adjacent the ports 38 and 3| in the body I0.

Referring to Figure 3, it will be noted that the ports 29 are drilledpassages which pass through the cylinder block thus communicating withthe bore 28. The cylinder block is also provided with the reduceddiameter bores 32, the function of which is to provide for a more orless gradual communication from the space between adjacent vanes andeither the inlet or the outlet port of the body ID.

The cylinder block 25 is retained against angular movement within thebody l by a pair of threaded locating pins 2'! which are threaded intothe body In and engage apertures in the block 26. The block 26 is alsoengaged by machined shoulders on the body 18 and the member I3 50 thatit is firmly and accurately retained in positon axially of the pumpcasing.

Referring to Figure 2, the rotor preferably rotates in acounter-clockwise direction thus transferring fluid from the inlet port30 to the discharge or outlet port 3|. In order to accommodate the fluidwhich leaks from the pumping zone into the body 10,.the bores 33 areprovided in the block 26 which communicate between the inlet port 30 andthe interior of the body Ill. The suction created within the inlet portthus draws the fluid from the casing [8 into the said inlet" port. Itwill be understood that other means could be provided for draining thecasing l8.

Referring to the vanes 25, these will be seen in Figure 2 to comprisesubstantially cylindrical, shouldered or stepped members adapted to fitwithin the shouldered bores 24. The vanes terminate at their upper endsin a double beveled peaked portion as at 34 so that a line contactexists between the said vane and the bore 28 of the block 26, and attheir opposite ends in a cylindrical projection of smaller diameter thanthe shouldered portion thereof which is slidably received in therelatively reduced portion of the bores 24. Abore 35 connects betweenone side of the peaked portion 34 and the lowermost area 36 of thecylindrical projection of the vane, while a bore 3'! connects from theother side of the said peaked portion to the shouldered or stepped area38 of the vane. The areas 35 and 38 are so proportioned as to be equaland, therefore, each equal to one-half of the proejcted area of the endof the vane.

Referring to Figure 4, it will be seen that the diameter of the shoulderportion of the vanes 25 is greater than the distance between the membersI1 and [9. The vane is provided with flats 39 on either side thereofwhich engage the facing surfaces of the members I1 and I9 and therebyretain the said vane against rotation while simultaneously providing aseal against leakage from one side of the vane to the other. It will beapparent that the flats 38 are effective to guide the vane only duringthe starting period of the rotor. After the vanes are in engagement withthe cylinder bore 28, the engagement of the peak 34 with the bore 28 iseffective to maintain the vanes against rotation.

Referring to Figure 5, the action of the balancing areas of the vane 25is illustrated. In this figure it is assumed that the left side of thevane is in a pressure zone while the right side thereof is in a suctionzone. The thrust on the left side of the vane is indicated by the solidarrows while the pressure on the suction side is indicated by the dottedarrows. The pressure from the pressure side is communicated through thebore 35 to the lower area 36 of the cylindrical projection which, beingequal to the projected area of the upper end of the vane to the left ofthe peak 34, balances off the thrust therefrom. Likewise, any pressurestanding on the right side of the end of the vane will be communicatedthrough the bore 31 to the stepped area 38. The area 38 beingeffectively equal to the area of the right side of the end of the vane,any thrust on the vane due to suction pressure is completely balancedout. It will be apparent that the vanes are in a continuous state offull hydraulic balance axially. The thrust of the vanes against theblock 26 will, therefore, be equal to the centrifugal force created bythe rotation of the rotor. This centrifugal force, while sufficient tomaintain the vanes in contact with the cylinder wall, is not sufficientto promote undue wear or scoring between the vanes and the cylinderbore.

The side thrust on the vanes due to the fact that pressure stands on oneside thereof is carried by the cylindrical surface of the vane and thebore in which it reciprocates. It will be apparent that the method ofthis invention of providing cylindrical vanes is of distinct advantageas regard this side thrust. Theside thrust which is developed on thevanes is distributed over a substantially greater area than would betrue if the vanes were flat. The unit compressive stress developed inthe vane and the bore over the bearing area is thus substantially lessthan that ordinarily encountered in vane pumps. This reduces wear andpromotes the free reciprocation of the vane within the bore. Also themachining of cylindrical bores and cylindrical vanes to any degree offit is much more readily accomplished than in the case of fiat vanes andslots.

While the block 26 isshown in Figure I to be retained between shoulderson the body In and the cover plate [3 with sealing members indicated at40 disposed therebetween, it will be apparent that other methods ofsupporting and sealing the block 26 are equally effective. Also, it willbe noted that the block 26 maybe rotated through by removing the pins2'!v so that, with the same direction of rotation, the pump will deliverpressure fluid from the port 30. instead of the port 3|.

Referring to Figure 6, an arrangement is shown whereby the pump may bemade variable delivery. This is accomplished by arranging' the block 26within the casing [0 in such a manner that the eccentricity of thecylinder bore 28 relaassassin 52 time to: the rotor [:1 may: be varied:Suitablecontroli means such as the; rods: til and are; providedwhichextend throughapertures in the casing I for shifting -the;block:26: The-rods: 41- and 32" may be attached to: anywsuitable manualorautomatic control means so thatthe; delivery; of the pump may be-selectively -varied int-response: to any givenstimulus.

In order to=providefluid comm-unication1between the bore 28 a-ndtheports 1 3G and: 31" in: the pumpcasing, there. are provided the flatvportions 43=and 44i within the said casing WhiChrBII- gage the flatportions 45 and 56 onthe block 2-6; The flats4'3--to-46,' inclusive, aresomachined that the block 28- exactly and: slidablyfits: beetween-the-flats on the casing I0 thus-inhibitingleakage therebetween.

Thebl'ock 26-is provided with the bores ZB and 32 as in the case of theblock 26 in Figure 2. It will beapparent that theblock 26 may be movedby therods'M and-' l-z froma position of full delivery in one direction,through neutral into a position of full d'elivery'i-n 'theoppositedirection.

Referringito Figure 7-,pthel mannerinfwhichg the block 26 is retainedwithin thezcasing' I fliisishown-l The casing ill is provided with, ashoulder d! which slidably engages the block 26 on one side. Theotherside of the block 2-6 is engaged by a surface '48 onthe-member I it, thelatter having a second-shoulder la-thereonwhich abuts a second shoulder50 in the casing- Ill; The engagement of the shoulders 4-9-and-5B-opposes the shoulders 4'1 and (98 so that the block 26' exactly andslidably fitstherebetween;

Also shown in Figures- 6*: and 7* is a modified vanestructure'whereinthe flats on either side of the" vane areeliminated andthe orientation of thevane is-secured by'means'of a pin- 5lwl1ich issetin a drilled holein thebottom of" the bore 24 andeccentnically'located-with, respect to said bore and extends into a hole52 in the vane 25. The pin- 5| angularly lccates the vane 25 sothat fitWhenthe lattermoves outwardly due to centrifugal force the peakedportion 34 engages the cylinder bore Z'B-i'napmpermanner.

A plan view of the vane is shown in Figure 8 and indicates the eccentriclocation of the pin 5| and the relationship of the vane 25 with therotor members I7 and l 9.

It will be apparent that various modifications may be made in thearrangement and construction of this device without in any Way departingfrom the spirit of this invention.

Accordingly, it will be understood that We wish to comprehend suchmodifications and substitution of equivalents as may be considered tocome within the scope of the appended claims and the invention.

Having thus fully described our invention, what We claim as new anddesire to secure by Letters Patent, is:

1. In a vane pump, a cylinder block having a bore therein, inlet andoutlet means for said bore, a rotor rotatable within said bore, flangeson said rotor adapted continuously and slidably to engage said cylinderblock on either side thereof, a plurality of shouldered bores in saidrotor, a plurality of vanes having inwardly facing shoulders slidablymounted in said bores, said vanes having transversely beveled outer endsthereon, means comprising flats on opposite sides of said vanes inengagement with said flanges for retaining said vanes against rotationrelative to said rotor each vane including, channel means hydraulicallyconnecting one side of said beveled end 6 portion withtheishouldenofssaid vane andzother channel means hydraulically.connecting the; oppositeside" ofz said". beveled: endportion, with r the opposite endi-of'saidvane.

2': As: an article. of manufacture, a, vane forfluid:v operable pumps;or motors: comprising asubstantially: cylindrical member having a doneble bevelfonx one endlthereof acyIindricaI'YprO- jecti'on: ontheotherendthereof' of: smaller diameter thantheibodyl portion ofsaidmember, said cylindrical? proj ection definin with the: body-portion of'sai'dmember a shoulder facing toward: the cylindrical projection, and:channel; means bydraulically: connecting one side. of said beveledportion with the shoulder and: the other side of said-1 beveled portion:with the end of-' said projection; the end. of said projection and saidshoulder having substantially: equal areas.-

3; Asan article of manufacture; a vane for. fluid operabl'epumpsormotors comprising, a

cylindrical-member having at step thereonfacing toward one endf of saidmember andformed' with a double bevelon: the opposite end thereof, atleastone fl'at portion on said opposite end at right: angles to saidbeveled portion, and'c-liannels extending through said memberandconnecting one side of said: bevel with the step on said member and theother side-0t said bevel with the first-named end of saidmember, saidstep and said first-named end having" substantially equalareas;

4i. In a rotaryvane-type pump; a cylinder having' inlet and outlet portstherein; arotor rotatable Within said cylinder and formed with apluralityof cylindrical radially disposed vanereceiving chambers, eachof" the vane-receiving chambers ofsaidrotor comprisin an-outerbore and arelatively reduced inner bore providing-an inward continuation of theouter bore; a plurality of shouldered vanes slidably carried with-r inthe chambers of said, rotor in close-fitting relation to the; Walls ofsaid bores," each of said vanes being" formed with an inner cylindricalend" portion extending within. the, inner bore. of said chamber. andterminating, in, a, flat, pressure-responsive area, an intermediatediametrically enlarged cylindrical portion slidably positioned Withinthe outer bore of said chamber and defining a pair of relatively opposedpressure-responsive areas, and a cylindrical outer end portionterminating in a pair of angularly related pressure-responsive areas,the angularly related areas on the outer ends of said vanes merging toform a peak on said vanes for wiping engagement with said cylinder, afirst channel in each of said vanes extending through the intermediatecylindrical portion thereof to establish communication between one ofthe said pair of angularly related areas disposed at the outer end ofsaid vane and the inner area of the said pair of opposedpressure-responsive areas defined by the intermediate cylindricalportion of said vane, and a second channel extending through each ofsaid vanes and estab-- lishing communication between the other of saidpair of angularly related areas on the outer end of the vane and theflat pressure-responsive area on the inner cylindrical portion of thevane, the various pressure-responsive areas of each vane being sized toprovide for the equalization of fiuid pressures acting thereon wherebyto maintain said vanes in a state of pressure equilibrium at all timesduring the operation of said pump.

- 5. In a rotary vane-type pump; a rotor formed with a plurality ofradially disposed stepped cylindrical vane-receiving chambers formedwith inner and outer bores of different diameters; and a plurality ofvanes freely reciprocable in said chambers and each comprising a body ofsubstantially circular transverse crosssectional configuration formedintermediate its ends with a diametrically enlarged cylindrical portiondisposed in wipin engagement with the walls of the outer bore of itschamber and defining on said body a pair of oppositely disposed fluidpressure-responsive faces, said body terminating at one end in a thirdpressure-responsive face and at its opposite end in a second pair ofangularly related pressure-responsive faces, a first channel in saidbody extending from a point adjacent to one of said second pair ofangularly related faces to the third pressure-responsive face, and asecond channel in said body extending through the diametrically enlargedportion thereof on the side adjacent the other of said second pair ofangularly related faces, the various pressure-responsive faces of saidbody being arranged to maintain said vanes in a state of pressureequilibrium when said rotor and vanes are operatively positioned in apump.

6. In a vane pump, a cylinder having inlet and outlet means, a rotorrotatable within said cylinder, a plurality of substantially radialshouldered bores in said rotor, a plurality of vanes slidably mounted insaid shouldered bores and each having a shoulder formed with a surfacefacing toward the center of said rotor, said vanes having beveled outerends thereon, means associated With said vanes for retaining the sameagainst rotation relative to said rotor so that said beveled end portionis retained substantially parallel to the axis of said cylinder, andchannel means in each vane hydraulically connect ing one side of thebeveled end portion thereof with the surface of the shoulder facing thecenter of said rotor and the other side of said beveled portion with theopposite end of said vane.

7. In a vane pump, a cylinder havin a bore therein and inlet and outletmeans for said bore, a rotor rotatably supported within said cylinder, apair of flanges attached to opposite sides of said rotor so as slidablyto engage said cylinder block on either side thereof, a, plurality ofsubstantially radial shouldered bores in said rotor, said bores having adiameter slightly greater than the transverse distance between saidflanges, a plurality of substantially cylindrical shouldered vanesslidable in said bores and having flats formed on the opposite sidesthereof so a to fit exactly and slidably between said flanges, theshoulder on said vanes facing inwardly, said vanes having transverselybeveled ends thereon, and channel means for each vane hydraulicallyconnecting the opposite sides of said beveled end portions with theopposite end of said vane and with the said shoulder thereof.

'NORMAN F. MACMILLIN. HOWARD M. PURCELL.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 983,754 Nichols Feb. 7, 19111,603,437 Wingquist Oct. 19, 1926 1,805,063 Wrona May 12, 1931 1,807,392Davis May 26, 1931 1,819,867 Carlton Aug. 18, 1931 2,137,708 Wilson eta1. Nov. 22, 1938 2,149,337 Deming Mar. 7, 1939 2,159,941 Guinness May23, 1939 2,335,284 Kendrick Nov. 30, 1943 2,354,076 Tucker et a1 July18, 1944 2,356,916 Brewster Aug. 29, 1944 FOREIGN PATENTS Number CountryDate 132,994 Switzerland July 16, 1929 166,871 Great Britain Jan. 5,1922 524,897 France May 23, 1921 722,961 France Jan. 8, 1932

